Generally, in image forming apparatuses for recording images by supplying a developer to an electrostatic latent image formed on a photosensitive member through a developing roller and transferring visible images formed on the photosensitive member to a recording medium, a cartridge-type process unit is employed in order to facilitate operations for maintenance, replacement, and the like (for example, see JP-A-10-105020).
In the above-described image forming apparatuses, a rotation driving unit is provided on the side of a process unit. In this case, the rotation driving unit rotates in a state in which it is connected to a driving source provided in a main body of the image forming apparatus, causing a photosensitive member or a developer roller to rotate. According to a structure of this image forming apparatus, by closing a cover provided to an opening for attaching or detaching the process unit, a rotation driving force generated by a driving source is transmitted to a rotation driving unit.
According to the above-mentioned image forming apparatus, even in a case in which the process unit is not mounted on the image forming apparatus at a correct location for the process unit to be mounted, or a different kind of a process unit not to be used in the corresponding image forming apparatus is mounted on the image forming apparatus, the cover of the imaging forming apparatus can be closed.
In this case, a driving source of the image forming apparatus or a rotation driving unit of the process unit, or the main body of the image forming apparatus or the process unit may be damaged.